Many projectile launchers require that a projectile be forcibly rammed into a launch tube in preparation for firing the projectile. Typically, the projectile must be stopped at a certain location in the launch tube and then restrained at that location until the projectile is to be launched. Then, at launch, the projectile must be released so that it can move freely in the launch tube under the force of a launch pressure applied to the aft end of the projectile. Thus, a restraint and release means must provide a two-part functionality. That is, it must be strong enough to brake and then restrain a rammed projectile, while also being weak enough to structurally fail so that the projectile is free to move in the launch tube when it is fired therefrom.